The basic oxygen furnace used in the steel industry usually has a rounded metal bottom, cylindrical metal side and a metal conical top portion with internal brick lining.
Because of the high temperatures involved, particularly at the vessel upper conical portion, it is necessary to provide a cooling system to prevent the conical portion from overheating and failing. See for example U.S. Pat. Nos. 3,304,075; 3,687,436; 3,719,355; 3,799,524; 3,817,504; and 3,895,783. Water is the usual cooling liquid although other liquids could be employed.
Existing cooling systems utilize flow passages whereby the coolant (water) flows upward from a lower header to an upper header and then back to a lower header. The upward and downward flow is against the cone shell. In this case, when the water flows downward against the shell, steam which may be created will want to move counter to the flow direction. This may block the flow.